Incandescing body for lighting purposes.



No. 817,734. PATENTED APR. 10,.1906,

w. VON' OLION. .INCANDESGING BODY FOR LIGHTING PURPOSES.

APPL/IOATION FILED MAY 31, 1902 lm m geneaas mat/h: cumin/ 13 nm'a/zfr/re waned/21m group.

. I [NI E/W01? F330. sit/yea.

s'rarris r rnivr r nc Wanner voN .eoiLroN, OF'CHARLO'FIENBURG, GERMANY, Asslenoa T0 smmns a HALSKE.AKTKENGESELLSCHAFT, OF BERLIN, GERMANY.

To (tZZ whom, it may concern:

Be it known that I- WERNER VON BOLTON, chemist, a subject of the Russian Emperor, residing at 69 Goethestrasse,Charlottenburg, near Berlin, Germany, have invented certain new and useiull mprovements in Incandescing Bodies for Lighting Purposes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in incandescing bodies for electric lamps.

The object of my invention is to provide an incandescing body which will have a hi h iight emitting eiiiciency, will give a light 0 a color suitable and leasing for illuminating purposes, will he s l ciently durable to meet commercial requirements, and can be manufactored at a reasonable cost.

Although many attempts have been made heretofore to produce an incandescing body jwluch would. have an appreciably higher lightemitting efiiciency than the. carbon glowers 111 general use up to the timeof my invention, such attempts had not been successful, so far as I am aware.

An incandescing body embodyin'gmy invention has such important advantages over the glowers heretoforelmowu as to render it entirely successiul.

After a lon series of experiments I have found that substantially pure metals of the vanadium group have characteristics which make them peculiarly advantageous as li htconstituents of'an illuminant. he and most important characteristic of ure metai cf the vanadium group is that its iightemitting eiheiency is very high compared with anything heretofore known. Another important characteristic of such pure metal is that the color of the light that 1s to say, its spectrum-is pleasing to the eye and satisfactory for purposes of illuminat on, t being the, continuous spectrum of an moandescent solid. in addition to these characteristiri s, such metals have a meltingpomt (particularly tantalum, w ch has an exceedingly high meltmg-pmrit-namely above 2,060" Qelsius) and arenot scattered by thermal and electrical action, as are carbon filaments, whiie at the same time possess- Speeification of Letters Patent. Application filed May 31,1902. Serial No. 1051.793.

true meta aucaoaossome eoov FOR mom-me, PUFiPOSESQ Patented April 10, 1906.

I ing sufficient' specific resistance to make them suitable for such purpose.

My invention consists in an incandescing body whose light-emitting pro erties are dependent upon the presence 0 pure metal of the vanadium group.

An incandescing body embodying my invention may consist wholly of one metal of the vanadium gro'u such as tantalum in its pure or substantial y pure metallic form, or may be formed by intermingling, mixing, or

alloying a plurality of such substantially pure metals of the vanadium roup.

' In the present application, althou h I claim enerical y an incandesc'in bo y' whose ight-emitting properties are dependent upon the resence of a'nfibstantiall pure metal of: t e vanadium "group, I 0 not .claim specifically an incandescing body. consisting whollyjof one such metal, as thatforms the subject-matter of m application, Serial N 0.

293,616, filed Decem or 28, 1905, divided outof this application by re uirement of the -Commissioner of Patents, t e s ecific claims of this application being base upon an insubstantially candescing body composed of a-Imxture or alloy of the vanadium group.

It is to be'obseryed that I use the term substantially pure metal of the vanadium oup. This is for the reason that there have -eretofore been known certain compounds called tantalum which were supposed to be the'metal tantalum; but which; as I have discovered, were not. The aforesaid socalled tantalum" was either an oxid, a hydrid, or a carbid of tantalum and in'every case had. properties quite difiere'nt from the I am the. first to produce pure metal of the of two or more substantially pure metals 1 vanadium group and the first to discover its remarkable properties as a light-emitting body. The roprties of the substantially pure metal 0 the vanadium grog are radically different from the matena hitherto known. While the latter was said to be brittle and could not be wrought, substantially pure metal of the said group is exceedingly ductile and can be wrought-that is to say; welded, hammered, rolled, and drawn m other words,. manipulated in a manner winch differentiates it essentially from the matefurther treatment.

tic mass may be pressed so as to. ta

are used, the resultinlg1 vention.

In order to first obtam a coherent metallic body or metal of the vanadium group, m x

the amorphous powder of such. a metal, in

which form the impure metal is commonly.

obtainable; with suitable binding substances, which may be volatile, and I have found that paraffin is a good and useful binding substance for this purpose. The resultin plase the the most convenient for I have also found b experiments that the amorphous powder 0 tantalum metal can be transformed into acoherent body by high pressure, binding substancet is necessary. to the pressure em loyed,1 obtain a more or less strong and co erent metallic body. If organic binding substances, such as paraliin, body is placed in an oven to drive out e binding substance. The body thus'obtained is then heated by shape which will be According means of an electric current in the absence 0 air or in vacuo. Under the influence of the heat produced is Y the electric current a sin tered or molten homogeneous metallic body is obtained which is ductile, and thus can be hammered, forged, rolled, or drawn to a wire,

and l. )rcfer to reduce the homogeneous metallic ody obtained in the above-described manner to rods or the like of suitable crosssection by pressing, rolling, or the like and then to draw Wires from sald rods, whereby a wrou ht metal of the vanadium group is obtaine the said. wires then being ready for use'as wrought filaments.-

The incandescing bodies obtained according to my said invention may be em'ployed in the usual Way in'a glass bulb in peace. It is found to be unnecessary to exhaust the bulb beyond the point at which no aureole appears.

The above process relates to the pr duction of an incandeicing body i vanadium group,

so that no one metal of the-vanadium, irgoup in a substantially pure condition. hereinbefore stated, an incandescing body of this kind not claimed specifically herein.

Instead of carrying out the starting with an amorphous pow er of one metal of the vanadium group I may use a. mixture of the amorphous powders of diflerent'metals of the vanadium group and treat this mixture as described above, thereby obtaining an incandescing body which is cornposed of a mixture or alloy of metal of the or after obtaining the subduotile metals separately the process described these may be mixed, intermingled, or alloyed, and from stantial pure and resultant product the desired incandescent bod may be formed by hammering, rolling, or rawing to produce the wrought filament of the compound metal.

In the accompanyingl draw avmg a illustrated a glow-lamp ament in one of the many forms in which my invention consisti of may be emhpiloyed, it being assumed that the particular tantalum and vanadium.

Having thus fully described my invention, what I claim is a 1. Ahomogeneous metallic lower for in.- candescent lights containing uctilejnetal of the vanad um group, the lightrcmitting properties of the glower being dueto the presence of this metal.

2. A glower for incandescent lights containing homogeneous ductile alloy of metals of the vanadium group, the lig -emitting properties of the glower being due to the presence of such alloy. k

3. A lower for incandescent lights con sisting 0 an alloy of metals of the vanadium P- 4. A glower for electric glow-lampscomposed o a wrought filament of an alloy oi metals of the vanadium group.

7 In testimony whereof I have afiixed my signature in presence of two witnesses.

WERNER VON BOLTON. Witnesses: I v

' HENRY Hasrnrg. Wornnmn Hauler.

recess by I have ament illustrated is composed oi 

